Articles of interest from the Fairfax County Park Authority

Tag Archives: Grist Mill

About six months ago, Colvin Run Mill entered a contest to win grant money through
the Fairfax County Park Foundation. We sought help, asking you to join the site’s supporters and cast votes through social media outlets on behalf of the mill. You met the challenge, in the manner of the old political joke, by voting early and often. The result was a fourth-place finish among 24 historic sites in the contest and a $75,000 grant for Colvin Run Mill, the largest grant in the site’s history.

Colvin Run Mill has actually been spinning slightly out of sync over the years – a bit like playing guitar with one string inappreciably out of tune. Inside the mill are two giant, horizontal power shafts called counter shafts. They are key parts in the system that turns the runner stone, a French buhr stone used for fine grinding. The runner stone is the top stone that turns above a stationary bedstone when the mill grinds grain. At Colvin Run, the first of those counter shafts connects to the second one through a metal attachment, sort of like railroad cars locking together. That second shaft powers the ‘country’ stone, a style of stone often used to grind corn.

At Colvin Run, that first shaft is slightly warped and thus unable to turn the second shaft. There wasn’t enough money designated to fix that problem when the mill restoration began in 1968, so Colvin Run has been turning only one millstone over the years.

We promised that if we earned some money from the Partners in Preservation contest that we’d use it to fix that and some other issues at the historic site. That would free up bond money that had been designated for mill repairs for other needs.

Now, we’re keeping our word. The Park Authority hired HITT Contracting, who turned to Ben Hassett and his Lynchburg company, B.E. Hassett-Millwrights, to lend a hand in the repairs at Colvin Run. Hassett-Millwrights specializes in repair, maintenance, restoration and reconstruction of wind-and water-powered agricultural and historic sites. The company has worked on historic mills in California, Maryland and Virginia, and will endeavor to preserve as much of Colvin Run’s original material as possible.

Hassett first removed the shims that locked the gears in place on the shaft, and then suspended those gears so that they hang freely. That allowed him to remove the estimated 800-pound counter shaft from the mill and take it back to his shop. It will be used as a guide for the creation of a new counter shaft that will be fashioned out of white oak, matching the material used in the original mill. The selected tree is at Hassett’s shop and was chosen with consideration for its growth pattern so that it is unlikely to twist and can withstand the torque it will endure in the mill. About 100 pounds of metalwork on each end of the counter shaft will be removed, re-milled if needed, and reused on the new shaft.

The next step is the one that has the staff at Colvin Run Mill excited. The new shaft will be attached to the second counter shaft and, with the warp removed from the system, that second counter shaft will turn the country stone. That stone has never turned at Colvin Run. The grinding station at which it will sit has run at least one time in the past, but no stones were in place at the time. The country stone will grind corn because its pattern does not produce flour as fine as the French buhr stone’s product.

Colvin Run staff and Hassett are documenting the process step-by-step with photos of the work along the way. That will preserve a record of the repairs being made now and provide a guideline for any future work the mill requires.

This current project, which continues the mill restoration that began in 1968, will last until late 2014. The current phase of work on the mill’s first floor is expected to be completed by spring so that public tours during the mill’s prime season won’t be affected. Subsequent work is planned on the building’s second and third floors. That will include designing and installing grain cleaning equipment, completing the mill’s system of flour delivery, completing an internal rope hoist, and changing some fittings to a more period-appropriate design.

So once again, thank you. The mill will soon be tuned and grinding again. With the help of county residents who cast votes in the Partners in Preservation contest, the Fairfax County Park Authority is able again to protect resources.